Linux is an operating system.It is similar to the unix os.
Basic linux command:
1. Ls :- This command is used to list all the files in the current working directory . Eg :- $ls
2. Rm :- This command is used to remove the file from the directory. Eg :- $rm filename
3.Rmdir :- This command is used remove directory . But it should not contain any file.Then only we can remove the directory
eg :-$rmdir directory name
4.Cat :- This command is used to create a file in the directory.
Eg :- $cat>filename (i.e.,)used to write the content in to the file.
eg :- $cat file .(i.e.,) used to display the content in the file

Linux is a computer operating system similar to Unix, mounted under the model of development and distribution of free and open source software. The defining component of Linux is the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. The Free Software Foundation uses the GNU / Linux name to describe the operating system, which has generated some controversy.

Linux was originally developed for personal computers based on the Intel x86 architecture, but has since been ported to more platforms than any other operating system. Due to the dominance of the Android OS based Linux-based kernel on smartphones, Linux has the largest installed base of all general-purpose operating systems. Linux is also the leading operating system in servers and other large iron systems, such as mainframe computers, and is used in 99.6% of TOP500 supercomputers. It is used in about 2.3% of desktop computers. The Chromebook, which works with the Linux OS based on the Linux kernel, dominates the US education market. K-12 and accounts for almost 20% of notebook sales of less than $ 300 in the United States. Linux also runs on embedded systems: devices whose operating system is normally built into the firmware and is highly tuned to the system. This includes TiVo and similar DVR devices, network routers, facility automation controls, televisions, video game consoles, and smartwatches. Many smartphones and tablets operate with Android and other derivatives of Linux.

The development of Linux is one of the most prominent examples of free software and open source collaboration. The underlying source code may be used, modified and distributed - commercially or non-commercially - by any person under the terms of their respective licenses, such as the GNU General Public License.

Typically, Linux is packaged in a form known as Linux distribution (or distro for short) for both the desktop and the server. Some of the most popular Linux distributions are Linux, CentOS, Debian, Fedora, Gentoo Linux, Linux Mint, Mageia, openSUSE and Ubuntu along with commercial distributions such as Red Hat Enterprise Linux and SUSE Linux Enterprise Server. Distributions include the Linux kernel, support utilities, and libraries, many of which are provided by the GNU Project, and usually a large amount of application software to meet the intended use of the distribution. Desktop Linux distributions include a windows system such as X11, Mir or a Wayland implementation, and a companion desktop environment such as GNOME or KDE Plasma 5; some distributions may also include a desktop with fewer resources, such as LXDE or Xfce. Distributions intended to run on servers can bypass all graphical environments in the standard installation and instead include other software to configure and operate a stack of solutions such as LAMP. Because Linux is freely redistributable, anyone can create a distribution for any intended use.